1. Field of the Invention
The present invention relates to a carburetor and, more particularly, an improvement of a carburetor for use with an internal combustion engine which incorporates intake manifold heating by exhaust gases.
2. Description of the Prior Art
In an internal combustion engine, especially an engine of a cross flow type, wherein the intake manifold, especially a riser portion thereof is heated by exhaust gases to improve startability and warming-up performance of the engine, there is a problem in that if the engine stops after it has been warmed-up, the carburetor receives heat from the riser portion by radiation and conduction, causing considerable increase in temperature of a float chamber and a flange portion of the carburetor, whereby vapour lock might occur in the fuel system over a wide range, including the carburetor. If such vapour lock occurs, problems such as rough idling of the engine due to misfire during its restarting and an increase of the combustible components in the exhaust gases, etc., are produced.